DESIR has been used successfully to determine the composition of milk (Núnez-Sánchez ˜ et al., 2008; Coppa et al., 2010) and perform pregnancy tests using the plasma of ewes (Andueza et al.,
2014)./
The aim of this work was to study the evolution of carotenoid and -tocopherol concentrations in plasma during the fattening period of beef cattle from different breeds that were finished on forage-based diets with different carotenoid and -tocopherol contents to check the feasibility of using them to trace forage-feeding in the visible and near infrared spectra./